Which one of the following enzymes is not composed of simple proteins?

Enzymes are the polymers of

Enzymes,which catalyse the joining of $C-O, C-S, C-N, P-O$ etc. bonds,are included in which of the following classes?

Which class of enzymes is involved in oxidation and reduction reactions?

According to the lock and key hypothesis,which complex is formed when an enzyme binds to a substrate?

Arrange the following steps of enzyme action in the correct order:
$I - E + P$
$II - ES$ complex
$III - EP$ complex
$IV - E + S$